RSV vaccines would be delivered to up to 7000 newborns and infants if the Canberra Liberals are elected in October.
The opposition has said they would spend $2.6 million to access the Beyfortus immunisation, which was approved by the Therapeutic Goods Administration last November.
Opposition Leader Elizabeth Lee said the immunisations would be available for next year's RSV season, in autumn and summer.
"This program will go a long way in protecting vulnerable newborns and infants against RSV and it is important we take action and provide these immunisations for Canberra babies," she said.
Respiratory syncytial virus is highly contagious, with symptoms including a runny nose, sore throat, cough, fever and aches. It is the number one cause of hospitalisation for children aged five and under in Australia.
There have been issues with vaccine supply and Population Health Minister Emma Davidson recently told the Assembly the levels of access to the vaccine varied.
"The levels of access that we have to vaccines are dependent on a number of factors around availability of the product in the market, and various programs that we can access it through as part of the national immunisation program as well," she said.
But opposition health spokeswoman Leanne Castley slammed the government, saying other states had been able to secure a sufficient supply and she said the vaccine should be available for all newborns.
"Incredibly, despite Beyfortus being approved by the Therapeutic Goods Administration last November, until last month ACT Health's website was advising Canberrans there was no immunisation to protect against RSV," she said.
"Other states including Queensland and Western Australia managed to secure sufficient supplies of Beyfortus to vaccinate newborns as well as vulnerable infants but the ACT failed to plan for this."
The ACT Health website says the vaccine is only available in Canberra hospitals through a NSW Health program.
Under the NSW program, the vaccine is offered to hospitalised infants who are premature, Aboriginal and Torres Strait Islander or other vulnerable infants with certain health conditions.